Thermostatically-controlled socket switch



April 20 1926. 1,581,233-

i R. D. SMITH THERMOSTATICALLY CONTROLLED SOCKET SWITCH 2 Sheets-Sh-ee'fV 1 Filed Dec. 5, 1920 April 20, 192e. 1,581,233

R. D. SMITH THERMOSTATICALLY CONTROLLED SOCKET SWITCH Fled Dec. .3, 1920 2 Sheets-Sheet 2 m my Patented Apr. 2li, i926,

cnn-an srn'r 'errant RAYMOND DSMlTI-I, 0F SCARSDALE, NEW YORK, ASSIGNO'R, BY MESNE ASSIGNMENTS,

TG TREMONT PRODUCTS CORPORATIQN, F BOSTON, MASS&GHUSETTS, .A CORPORA- TIN 0F MASSACHUSETTS.

'THERMGSTATICLLY- CONTBOLLED SCKET (Sl/WITCH.

Application led December 3, 1920. .Serial No. 428,16).

To all eli/tom t m ay concern.'

Be it known that l, RAYMOND D. SMITH, a citizen of the United States, and resident of Scarsdale, in the countyf 1Westchester' and State of Maw York, halve invented cer tainnew and useful Improvements -in Thermostatically-Controlled Socket Switches.

@ne object of the present improvement is the provision of a pull chain control in an electric lamp socket or other type of switch employing a controlling thermostat to automatically delay the circuit breaking action when the switch has been manually actuated to extinguish thelight.

The present invention also includes novel features of arrangement and construction in the switch mechanism per se, aimed to render asocket switch with the above feature more durable in use and cheaper to manufacture.

Much of the novelty here concerned, constitutes improvements specifically applicable in the form vof thermostatically controlled socket switches such as is illustrated and described in United States Patent No. 1,328,478 granted J an. 20, i920 wherein `the switch ,controlling thermostat operates a latch, and speciicall constitutes such latch, normally positioned to intercept the circuit-breaking movement ofV one or the switch contact members.

. A general simplification of the Contact controlling mechanism is contemplated by the present improvements whereby much of the requirement for skill andvaccuracy in assembling shall be eliminated. The present improvement, furthermore, provides a switch mechanism wherein there is no possibility vof leaving the contact parts in a position to are or' burn.

A possible and preferred embodiment of the present invention is illustrated in the accompanying sheets of drawings wherein, Fig. l is an elevation of the complete socket cut away to better show the interior parts. Fig. 2 is a section 'taken 'on the plane 2-2 of Fig. l Alooking' in the direction of arrows. Fig. 3 is a View looking in the same direction as Fig. 2 but takenin section on the planes 3 3 in Fig. 1. Fig. 4c. shows details of construction and a diilerent position. of certain parts in Fig. 2. Fig. 5 is a fragmentary View looking from the left at Fig. l, certain parts above thethermostat and conswitch with casing and lower threaded shell directly after the oni actuation of the pull chain, but before the circuit has been automatically broken. Fig. 9 is a perspective downwardvieW of the thermostat, its cooperating contact member, and the bracket on which both are mounted. Fig. l0 is a perspective upward view of the pull chain operated .segment and contact loperating cam assembled therewith. Fig. llpis a detailed perspective view ofthe pivot washer enlarged. Fig. l2 is a similar perspective view of the pivot screw. Fig. 1 3 shows on a greatly enlarged scale the anchorage of a lead wire to an insulated strap about the thermostat. Fig. lll shows the anchorage to this same strap of a fine resistance wire which heats the thermostat. 1 Fig. l5, shows the anchorage for the resistance wire at its grounded end, Fig. i6 shows the developed shape of the thin, soft sheet metal 'strap for elec trical connection of the tine resistance wire. Each part when appearing in different 'views of the drawings is designated by the same reference character.

In Figli the usual upper porcelain button l0 and lower porcelain button 11 are secured f in spaced relation by four bracket members as follows: the main contact bracket 12, the auxiliary contact bracket i3,

bracket lll, and the thermomat bracket 15,

each of which engages with suitable iocatirng grooves on boththe opper andlower porcelain buttons.

The main contact bracket l2 carries the main spring-leaf contact lo. The auxiliary contact bracket i3 carries the auatiiiaryv vspringfleat contact 17, to the end owhich is secured an insulating `facing i8 by eyelet 19 or other suitable form of fastening. The center bracket lll is plaim'servingto electrically connect the nppercentralcontact washer' 20 through screw 2l with the lower central Contact tongue 22 through screw 23. T hiscenter bracket thus forms one side of the line through the socket indicated-.by the numeral 24 in Figures 6 to 8 inclusive.

.the center roo ;' tibi The thermostat 25 and co-opera'ting spring-leaf contact 26 are riveted at dillerent places to the bracket 15,- as 4more plainly shown in Figure 9, andr by means of the preferred construction et a rectangular riveting boss struck up from the metal ot the 'bracket itself.,

Thethermostat 25 carries a tight fitting sleeve 23 of suitable insulating material, such as asbestos paper.l on which is wound the required number of turns ot' a small resist-ance Wire 29 in insulated relation to the thermostat and anchored at each end in a. manner hereinafter to be described. b

The thermostat bracket 15 has a centrally disposed terminal 30, on which is mounted by means of a novel pivotal construction,tl1el pull-chain operated cam 31, which coop.y

erates with both contacts 17 and 26 for a purpose` and in a manner hereinafter fully described. Uri-standing ear portions 32. 32 (Fig. 10) of the cam .31 are rigidly secured to thrust plate 33 and to a superposed fibre' segment 34, by two eyelets, 35, 35, as plainly shown in Figure 10, Where the libre segment 34 is shown as also provided with a peripheral chain gui-de 3G having bent terminals 3'( each end containing an anchorage slot 33 lor the ball chain. The chain guide 36 is fastened to the bre segment 34 by means or 11p-standing prongs 39 (see Figure 5) Which project through corresponding slots in the libre segment and are bent over tlat on the upper surface of saine, in the .Wellknown manner. v'

"ilvvo operatively separate chains 42 and 43 are employed for oscillating the breseglnient 34 by alternate pulling thereon, the

upon the centrally disposed terminal ot thermostat bracket 15 (ses .Fign 3) consists or the pivot screw 45 shown in enlarged detail in Fig. 12 and the spring-armed pivot` Washer 45 shown in enlarged detail in liig.y

1l, and carrying the downward bent lock tongue 4J" tor engagement with the notch 48 in bracket terminal 30.

The parts just describe-dasseinble in the tollovvingy manner., First, washer 43 is placed against the upper surface of bracket terminal 30 with tongue'4? engaging notch 43. Screw 4t2 is then. set up in the tapped hole 99\in'braclret terminus() meines 'so that the flattened head 100 of screw 45 engages the hub portion v.101 of the washer.

46 securing the latter in place. llhe reduced end 1020i screw 45 then protrudes below the bracket terminus 30 an' amount preferably equal to the thickness of the sheet metal from which cam 31 is formed. The 'space between the seating portion 103; of cam 31 and the thrust plate 33, however, is slightly less than.

is the normal overall distance from the lower face of bracket terminus 30 to the, highest point of th spring arms 104, 104 of washer 46 so that in sliding the cam and segment lstructure 3], 33, 34 onto its pivot the spring arms 104 are' depressed su'liciently to allow the seat portion 103 ot" cani. 31 to slide past the protruding end 102 of screw 45 until the pivot hole 105 in cam 31 comes to register with the said end 102 of screiy 45, at which time 'the action of springarms 104 snaps the cam seat 103 up against the lower face of bracket terminus 30 and into'its normal assembled position shown in Figs. 1 and 5;- the spring arms 104, thereafter, acting to keep the cam 31 in place and pivoted on the end of screw 45 and resiliently pressed up wardly against the bracket terminus v30.

This novel hinge construction is obviously usable in other connections .than electric switches but is of particular advantagel so used because giving a smooth and positive pivotal connection offering desired 4frictional resistance and requiring for its assemblage by unskilled labor no tools other than the fingers of the operator. No reliance is had upon the Workmanls skill to properly adjust tension, and the relation of the parts when assembled is assuredly accurate. l "lt is pointed out in connection with. the pivotal construction above described that the bending ofcam ears 32, 32 respectively in different angular planes gives more strength and rigidity With the desirable thin gauge metal employed than Would otherwise be possible, and that the presence of thrust plate l33 relieves 'libre segment 34 from all flexural strain, beingitselif ullyinsulated by the libre piece frompossible contact with electrically alive parts secured to the upper porcelain 10. A removable Screw such as 45 need not necessarily be employed to form the pivot projection102, as same could equally lle Well be ormedby metal struck downl 'from v the bracket terminal/30, or in other suitable manner. v f

-lhguares 13- and 14 show the preferred method employed for anchoring the insulated end of elicate resistance vvire 29 for protecting the same, While insuring goed mechanical. and electrical contact. A thin strap V is employed which is originally of the shape shown in Fig. 16, and which bends over the insulating jacket or sleeve 23 and is locked by bending over tongue `116, around-'which the 'copper lead Wire 117 is wound before pressing into place.

`The other end of lead wire 117 extends to line hair-like resista-nce wire 29, itself, ex-` The re-j sistance wire 20 is wound about another. tongue 113 of tlv'ie same strap 115 on the tended to contact with bracket 13.

opposite side of the thermostat, which when pressed down against the thermo jacket gives secure electrical contact and protective mechanical fastening for this end of the resistance wire. The other end of resistance wire 29 is wound under the protruding ends of a thin staple 11S) inserted through a narrow slot in the thermostat, these end-s being then pressed down to secure the wire in place and to establish good electrical contact for grounding to the thermostat.

The switchmechanism above described, including the porcelain buttons 10 .and 11, is capped by a male screw shell 106 and retaining porcelain block 10.7, said screw shell 106 having electrical connection with main contact bracket 12 yby means of screw 106 but. being insulated from all other holding screws penetrating upper porcelain button 10. Depending from lower porcelain button 11 is the usual female screw shell, or lamp receptacle, 109 having electrical connection with the auxiliary contact bracket 13 by means of the screw 110 but being insulated from all other fastening screws penetrating lower porcelain button 11.

The switch is enclosed as vusual within the casing 111 and paper lining 112, the former being fastened by 2 screws (not shown) which penetrate the casing 111 and .screw into tapped holes 113 in bracket members 114 secured in diametrically opposite relation to the upper porcelain 10 while insulated from all electrically alive parts. The operation of my improved thermostatically controlled socket switch is as follows:

-In the full olf position of the switch, the parts assume the relation in Fig. 6 at which time the chain rider 41 is down and .the chain terminal 44 is upf-the pull segment 34 occupying its full line position in Fig. 3 corresponding to the position of cam 31 shown in Fig. 6. To turn the light o n, or

. establish the lamp permanently in circuit,

the ball terminal 44 is pulled, swinging the pull segment 34 to its dotted position in Fig. 3 and cam 31 and switch contacts into their relation shown in F 7 where current passes from main contact 16 to Contact member 26 to cani 31 to auxiliary contact 17 through' bracket 13 and screw 110 to female screw shell 109. to one side of the lam'p,tre

turning straigh through the socketA by path 24 (see Figs. 6 to 8) composed of the tongue `\22, screw 23, bracket 14, screw 21 and washer 20, as hereinbefore described. lVhen the chain rider 41 is subsequently pulled for extinguishing the lamp thesegment 34 isv thrown to 'its full-line position in F ig. 3 and the cam 31 and several contact members assume the relative position .shown in Fig. 3 where the thermostat 25 retains Contact member 26 in contact with main contact 16 while the cam 31 has brokencontact with eyelct 15) by sliding on tothe insulating facing 18. The only path for the current now is from main contact 16 to Contact member 26 to the thermostat 25 through resistance wire 29 to auxiliary contact bracket 13 and thence through the lamp and back through the socket as before, it being seenV that here the resistance wire 29 is thrown in series with the lamp and is thereby heated, `ener1 gizing the thermostat 25 to perform a curva" ture-opening movement which retracts its freestagd from the tip of Contact member 26, pernutting the latter to snap away from contact 16' into its full otl position shown inf Fig. 6, wherein all circuit through the socket has been broken and the switch is ready for subsequent actuation to turn on the light. An interval of delav is thus interposed between the act of pulling the chain rider 42 and the actual circuit breaking action of the switch equal to the time required to'heat the thermostat 25 for effecting escapement of the contact men1be1'26.- In practice,'this time can readily be varied between 15 seconds and two or three minutesthrough variation of the electrical resistance of wire 29 and of the amount of engagement between the thermostat 25 and the tipend of contact member 26. It is understood that thermostat 25 possesses sufiicient elasticity to enable it tol yield when normallycool, like a latch, for permitting the passage of contact member 26 from its position in Fig. 6 to its cir cuit making position in Fig. 7.

' Specic advantages provided lby the present improvement reside in the arrangement of auxiliary contact 17 wherein the `latter constantly presses against a wiping portion of cam 31 opposing the latters movement from its position in Fig. 6 to its position in Fig. 7 until the cam has moved well into contact with eyelet 19. The leaving of cam 31 in a position forcing contact'member 26 linto arcing proximity with main contact 16,is'thus impossible, auxiliary contact 17 adding its tendency to that of the normalresiliency in contact member 26, for this' purpose, which latter alone is inadequate when made of desirablylight gauge spring metal, Y p

An improvement ofequalvalue is repre#` sented in the novel form hereby -given to' vthe main contact 16. Y A spring-leaf contact has heretofore 'been employedv` for this purportion rom bracket pose which performed its necessary yield-l ing to accommodate the latchinrr action of member 26, by ,flexing resilientl-iy from its `point of fastening to bracket 12. rl`he operative tendency of this relation of parts 1s to Y l of contact 16 is, in this arrangement, across the path of movement of member 26, the desirably quick break of the circuit is secured when these two contacts snap apart.

The various parts with their manner of assemblage hereinbefore described are for the most part readily producible from sheet metal through power press production methods making their accuracy dependable and their manufacture economical.v f

lt will be understood that the features of improvement here concerned are of a nature. lending themselves to embodiment in manykinds of switches other than electriclamp sockets of the particular form shown and to usey with mechanisms for other purposes so that the following claims are in 4 nti way intended to limit the forms of the inventions defined to the precise showing ini'- drawings. y

' `What lt claim as new is:

1. A lamp socket `switch having a' casing and switch operating instrumentalirties, the

latter including contacts, a thermostat disposed circumferentially in the plane vvof said contacts a\ contact-controlling member, a pull-chain-operated segment pivoted -to swing in a plane adjacent said thermostat and contacts connected to saidmember and wholly enclosed, within the casing, operatively dierent chains connected to said segment for oscillating the same by alternate pulling on said chains, and thermostatic control mechanism operating to delay the circuit-breaking movement ef the switch responsive to the manual actuation thereof.

2. A lamp socket switch having a casing and switch operating instrumentalities, the latter including contacts, a thermostat disposed circumferentially in the plane of said contacts a contact-controlling member pivoted to swingin the plane of said contacts and having `an actuating, segment removed from .said plane, operatively different flexible pull members extending into the .casing in a plane with said segment for oscillating the contact-controlling member by alternate aeenass pulling thereon, I mechanism operating to delay the circuitbreaking movement of the switch responsive to themanual actuation thereof.

3. A lamp socket switch having'spaced porcelains contacts operating therebetween, a contact-controlling member, brackets cennectin said porcelaine and one aiordinga pivot or said member a pull segment connected to the member andl having a ,greater afid'theremostatic control path of swing than the segmental space between said brackets, two operatively separate ilegible pull members connected 'to opposite ends of said segment for oscillating the sameand a thermostatic Contact control mechanism. y

LA lamp socket switch ,having spaced porcel-ains Acontacts operating therebetween, a contact-controlling member, brackets lconnecting saidgporcelains an oscillatory pull chain segment for actuating said member and having a greater are of travel than the `space between adjacent brackets, a pull chain for moving said segment, and thermostatic control means to delay the circuitbreaking movement of the contact .responsive to manilal'actuation thereof.

A lamp socket switch havingv spaced porcelains and a removable enclosing casing and ,having also 'switch operating instrumentalities, the same including a pivoted combined kcam-and-segment member, two

operatively separate pull chains connected to said member for oscillating the same,-a bell mouth guide for guiding said chains through sa'id casing and helping'to space and supportsaid porcelains, and thermostatic control 4mechanism operative to delaythe circuit-breakinglmoveinent of the switch yresponsive 'to the manual actuation thereof.

6. A lamp socket switch having 'spaced porcelains and a removable enclosing casing and switch operating instrumentalities, including a controlling member, a segment for actuating said member, a flexible pull member connected to said segment, a bell mouthed guide for said pull member extendiai lill@ ing between and helping to space and support said porcelains, and thermostatic control Iiiechanism to delay circuit-breaking' movement of the switch .responsive to the manual actuation thereof.

"7.' A pull-chain operated velectric switch mechanism having switch contacts designed to occupy a cylindrical enclosure and einbodylng a curved switch-controlling thermostatic band disposed eircumferentially of said enclosure; and a pull-chain operated segment for controlling the switch contacts, said segment oscillating in the direction of curvature of said thermostatic band and in a plne adjacent theedge thereof.

8. In a thermostatically controlled pullchain socket .switch including a ivoted switch-operating segment to which 'f e pull chain is attached, the lrelative arrangement of a controlling thermostatic band and of said operating segment wherein the former is curved and disposed substantially circumferentially of the pivot of the latter and wherein said operating segment -has a peripheral edge adjacent to and conforming to the curved' edge of said thermostatic band.

9. A socket switch mechanism embodying in combination a socket body, switch contacts, a curved thermostatic band arranged to govern, in part, the movement ofthe switch contacts responsive to manual actuation of the switch, a pivoted switch-operating segment having an anchorage for two Aoperat1vely separate pull chains at respectively opposite peripheral ends, 'and carrying a periphera channeled guide for said chains; a chain-outlet bell-guide secured to the socket body in a position opposite and closely adjacent the segment-carried chain guide, so that said segment is oscillated by alternate pulling on said separate chains.

10. A pull-chain operated switch embodying, in combination; switch contacts, top

- and bottom insulating buttonsv connected by metallic bracket members secured thereto, one of said members having a flattened terminal' disposed parallel to said buttons and between and spaced from same; and a pull operated member for actuating the switch contacts having a forked hub portion A adapted to straddle thesaid bracket terminal for pivotal mounting thereon together with a thermostatic device to govern in part the switch contacts. y

11.*A socket switch havingswitch contacts, a bracketterminal; a screw carried in y a tapped hole substantially central of said terminal and having its end protruding therefrom, a spring-armed washer clamped under the head of said screw and aga-inst the face of said bracket terminal opposite the protruding end of said screw, a pivoting` member for controlling said contacts having its hub formed by two-spaced flanges one of which has a hole fitting the protruding end` of said screw and the other of which takes the thrust of sa-id Aspring-armed washer,- the action of said washer pressmg the first mentioned flange against the said bracket terminal and maintaining pivotal engagement between saidl hole and the protruding end of Said screw and a thermostatic device to govern in part the switch contacts.

12. A socket switch having switch con-I tacts, a bracket terminal; a pivot projec- 'tion on the face of said terminal and sub' stantially central thereof; an axially actingr sprin member bearing against the face of said racket terminal opposite said projection; a pivoting member for controllingzthe contacts having its hub formed by twospaced flanges, one of which has a hole litvices acting normally to maintain pivotal l engagement between the controlling member and its support but yieldable to'permit intentionable displacement laterally with relation thereto, and ,thermostatic -mechanism to govern in part said contacts.

14. A socket switch having switch contacts, a rotatable contact controlling member and bearing seat on which it is pivotally supported, resilient means exerting an axial thrust to maintain pivotal engagement but yieldable to permit removal of said contact controlling member from said bearing seat orl installation thereon, and thermostatic mechanism to govern in part said contacts.

15. In an electric switch, in combination; a leaf contact member, a latch to retain said member in a sprung position; acanL for forcing said contact into said position, andv adapted to retract from contact with said member when the latter is held by Said latch; and resilient means comprising anelectrically active cbntact and acting to hold said cam fully retracted from said member whenthe latter is retained by said latch and thermostatic means for controlling said lio latch; and resilient means comprising an electrically active contact and acting to hold said cam fully retracted from said member after its said quarter turn and thermostatic means for controlling said latch.v

17. In an electric switch, the combination with a spring contact member, a rotatable `wiper contact movable intoand out of engagement .with said member and adapted to force the latter into sprung position, a therinostatically controlled device to retain said Contact member in its sprung position, ,and means comprising an electrically active contact tending to restore the wiper contact to its disengaged position.

18. In an electric switch, the combination with a spring contact member, a rotatable wiper contact movable into and out of engagement with said member and adapted to force the latter into sprung position, and a locate said contact-carrying member in defi-f i thermostatically controlled device to retain' and disengaged'positions and to restore it to.

its disengaged position in the event of an incomplete movement toward its engaging position.

-19. In an electric switch. the combination l with a spring contact member, a rotatable wiper contact movable into Vand ont of 'en- ,gagement with said member and adapted to force the latter into sprung position, a ther,-

mostatically controlled device to retain 'said member 1n its sprung position, and a resili ent device embodying an electrically active contactoperatively related to .said wiper contact and acting both to locate said contact definitely in its engaged and disengaged positions and to restore it to its disengaged position lin, the event of an incomplete movel ment toward its engaging position.

20. In an electric switch, the combination with a spring contact member, a rotatable wiper contact movable into and out ofen-l gagement with said member and adapted to `force the latter into sprungposition, and a thermostatically controlled device to retain said member in its'sprung position, said switch being also 'provided with an auxiliary Contact engaged by said wiper contact, said auxiliary contact being resilient and serving to restore said wiper contact. to its position of` disengagement from said con tact member in the event of an incomplete Vmovement toward its engaging position.

-2l. In an electric switch, the combination with a spring-leaf contact, a rotatable contact-actuating member.` forv `engaging the same, manual means for moving said member, thermostatically controlled mechanism to govern in part said contact, and'm'eans comprisin an auxillary contact and tending norma ly to restore the contact-actuating member to a position of contact disengagement. 7

f 22. In an electric switch, the combination witha main spring leaf contact, a rotatable contact-actuating member for engaging the same manual ymeans for moving said member, thermostatically controlled mechanism to govern in part said Contact, and means to nite positions of engagement or disengagement with said stationary contact, compris-- ing vank vauxiliary and electrically active springfleaf contact.

23. An electric switch having in combination contacts including a rotatable conductive cam, and a spring leaf contact member i co-operatingtherewith, an insulatin facing secured to the surface` of said mem er adjacent said cam by a conductive fastening,

` either said facing or its said conductive fastening being at all times'pressed into contact with said-cam in respectlvely. diderent posiing in part said contacts.

25. In an electric switch, a spring-leaf contact designed to be wipingly engaged by a co-operatingmovable Contact member and forithis purpose provided with a lengthwise stiffening' formation7 extending vfrom its] point/ of' mounting to a resilient terminalportion adaptedto contact resilientlyfwith o said member and a thermostatically conl trolled device for governing contacts. f

one of said 26. In an electric switch, the combination with a spring leaf contact, a second spring leaf'ccntact, amovable contact controlling member adapted by its movement to force the second contact into engagement with they first contact, and a thermostatically controlling device temporarily to hold the contacts in their sprung position of engagement, said second contact when released having a restoring movement transverse to tljel restoring -movement of the first contact.

27. In an electric switch, the combi-nation with a spring leafcont-act, a second'spring leaf contact, a movable contactcontrolling' member adapted byits movement to' force the second contact into engagementwiththe first Contact, anda thermostatically controlv ling device temporarily tohold the contacts in their sprung position of engagement, said contacts when released having 'restoring movements in different directions. y Signed at Boston, in the county of Suffolk and Commonwealth of Massachusetts, this-29th day of November, 1920.y 'Y

RAYMOND D., SMITH. 

